Water-saving device

ABSTRACT

A water-saving device includes an attachment cover  2  that can be mounted to a tap  1  or the like, a water-saving piece  6  that is internally fitted to the attachment cover  2  and has at least one water discharge hole  62 , and a watertight gasket  3  for preventing a water leak between the tap  1  or the like and the attachment cover  2 , wherein a pressure reducing piece  4  is disposed between the attachment cover  2  and the water-saving piece  6 , and in the pressure reducing piece  4  is formed a flow path changing hole  42  that forcibly changes the direction of water supplied from a water discharge means of the tap  1  or the like to reduce water pressure.

TECHNICAL FIELD

The present invention relates to a water-saving device that can be attached to a tap for discharging water (hereinafter simply referred to as “tap”), such as a swivel faucet, a mixing faucet, or an automatic faucet. This device not only has a water-saving effect but is also capable of discharging water that feels soft to the hand or body.

BACKGROUND ART

Existing water-saving devices are capable of saving water by suppressing the discharge rate of water without changing the usage feel of a faucet. Examples of such water-saving devices include an attachment cover that can be mounted to a tap or the like for discharging water and a watertight gasket for preventing a water leak that is provided between the tap or the like, and in the attachment cover, a cylindrical water-saving piece having at least one water passage hole is internally fitted in the attachment cover has been proposed (e.g., see Patent Document 1).

[Patent Document 1] JP H9-95985A

SUMMARY OF THE INVENTION Technical Problem

The proposed water-saving device is preferable to the existing ones in that simply by attaching this water-saving device to a tap for discharging water, the discharge rate of water spouted from that tap can be suppressed by the water passage hole formed in the water-saving piece with the same opening/closing operation of a faucet as a conventional operation, and accordingly water can be saved.

However, although water can be saved by suppressing water discharged from the water passage hole of the water-saving piece with a faucet, the operation of the faucet is difficult because a delicate adjustment is required, and the force of water discharged (water pressure) is strong, so that water that has hit the skin of a user may splash to stain the vicinity or wet a cuff portion of clothes, and other unfavorable situations may occur. Moreover, there is a problem in that for users having tender skin, such as infants and women, water having a strong force is excessively irritating to the skin.

Indeed, a shut-off valve can be operated in order to suppress the force of water (water pressure), but this results in burdensome operations of, for example, fully opening the shut-off valve during a period in which the supply of water should be limited and tightening the shut-off valve for other periods. Moreover, in this case, the original purpose of the water-saving piece, the saving of water by suppressing the discharge rate of water without changing the usage feel of a faucet, cannot be achieved.

Furthermore, since the volume and pressure of water spouted from a tap or the like are not necessarily constant and the supplied water is not spouted with the same rate or the same pressure, depending on conditions, such as the location or the floor level in a building or the water supply status, it has been difficult to discharge water from the water passage hole of the water-saving piece at a constant rate or a constant pressure.

The present invention solves the above-described problems and provides a water-saving device that can improve the usage feel without adjusting a shut-off valve, that is, save water by suppressing the discharge rate of water without making an adjustment of the shut-off valve every single time, stably discharge water without being influenced by variations in water volume and water pressure of the water supply status by suppressing the water volume and water pressure, and furthermore, provide discharged water having a soft feel to the user.

Solution to Problem

In order to solve the above-described problems, a water-saving device of the present invention can be removably mounted to a water outlet and includes a pressure control means and a water discharge means that is provided downstream of this pressure control means and has a water discharge hole, wherein water supplied to a faucet with an appropriate pressure passes through the pressure control means and thus is controlled to have an appropriate water pressure, and the controlled water is discharged from the water discharge hole in appropriate water volumes and in an appropriate discharge form.

The pressure control means is a means for controlling the pressure by automatically reducing the water pressure in a process in which supplied water supplied by a primary water pressure passes through the water-saving device from inside the water outlet at the tip of the tap. In other words, the pressure control means has at least one water passage hole for reducing the primary water pressure in the water-saving device so that water can only flow downward by passing through the water passage hole. Specific examples of the pressure control means include those having a flow path changing channel that forcibly changes the flow direction of supplied water to effect pressure reduction, those composed of a porous material and those composed of a rubber-like sheet material having at least one water passage hole can be adopted.

The water discharge means has at least one water discharge hole that is formed so as to extend from the pressure control means side and be connected with the outside and the water discharge hole can also have an appropriate hole form such as the form of a cylinder, a polygonal column, or a cylindrical tube. Preferably, the face on a side of the water discharge means that is exposed to outside air, the downstream end face, is concave or convex.

Preferably, the water-saving device of the present invention has a pressure adjustment means that adjusts the water pressure in a stepwise or continuous manner.

The pressure adjustment means is configured so that the water pressure or the water volume can be externally adjusted in a simple manner to set the force, volume, speed, and the like of released water without the need to disassemble the water-saving device.

In the water-saving device of the present invention, a primary water pressure on the upstream side of the pressure control means is reduced to a predetermined water pressure (hereinafter referred to as pressure-reduced water) by the water passage hole to create a secondary water pressure on the downstream side of the pressure control means, and water is released from the water discharge hole by this secondary water pressure.

Therefore, the water pressure or the volume of water released can be controlled at a tip portion of the water outlet without the need to operate a main valve or a shut-off valve.

Advantageous Effects of the Invention

According to the water-saving device of the present invention, an appropriate secondary water pressure can be automatically created between the pressure control means and the water discharge means, and this secondary water pressure enables water to be released from the water discharge hole formed in the water discharge means in an appropriate discharge form with a great water-saving effect.

Thus, water discharged through the water-saving device of the present invention (hereinafter referred to as buffered water) is not only gentle to the skin even when it directly hits the skin but also has a beautiful appearance, and in particular, provides such an effect that irritation to the skin can be minimized for the users having tender skin, such as infants and women.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an exploded perspective view showing an embodiment of a water-saving device according to the present invention.

FIG. 2 is an exploded vertical sectional view of the water-saving device shown in FIG. 1.

FIG. 3 is an enlarged sectional view of a use state showing a state in which the water-saving device of the present invention shown in FIGS. 1 and 2 is attached to a tap or the like.

FIG. 4 is an exploded vertical sectional view showing another embodiment of the water-saving device according to the present invention.

FIG. 5 a is a bottom view of a water discharge means, and FIG. 5( b) is a vertical sectional view of the water-saving device shown in FIG. 4.

FIG. 6 is an exploded vertical sectional view showing another embodiment of the water-saving device according to the present invention.

FIG. 7( a) is a vertical sectional view of the water-saving device shown in FIG. 6, and FIG. 7( b) is a bottom view of a water discharge means.

FIG. 8 is an exploded vertical sectional view showing another embodiment of the water-saving device according to the present invention.

FIG. 9 is a vertical sectional view of the water-saving device shown in FIG. 6.

FIG. 10 is an exploded vertical sectional view showing another embodiment of the water-saving device according to the present invention.

FIG. 11( a) is a vertical sectional view of the water-saving device shown in FIG. 10, and FIG. 11( b) is a bottom view of a water discharge means.

FIG. 12 is an exploded vertical sectional view showing another embodiment of the water-saving device according to the present invention.

FIG. 13( a) is a vertical sectional view of the water-saving device before a water pressure acts thereon, and FIG. 13( b) is a vertical sectional view of the water-saving device in a state in which a water pressure is acting thereon.

FIG. 14( a) is a vertical sectional view showing another embodiment of the water-saving device according to the present invention, and FIG. 14( b) is a bottom view of a water discharge means.

FIG. 15( a) is a vertical sectional view showing another embodiment of the water-saving device according to the present invention, FIG. 15( b) is a plan view of a water discharge means, and FIG. 15( c) is a bottom view of the water discharge means.

FIG. 16( a) is a vertical sectional view showing another embodiment of the water-saving device according to the present invention, FIG. 16( b) is a plan view of a water discharge means, and FIG. 16( c) is a bottom view of the water discharge means.

FIG. 17( a) is a vertical sectional view showing another embodiment of the water-saving device according to the present invention, and FIG. 17( b) is a sectional view of a relevant part of a water discharge means.

FIG. 18( a) is a vertical sectional view showing another embodiment of the water-saving device according to the present invention, and FIG. 18( b) is a sectional view of a relevant part of a water discharge means.

FIG. 19( a) is a vertical sectional view showing another embodiment of the water-saving device according to the present invention, and FIG. 19( b) is a sectional view of a relevant part of a water discharge means.

FIG. 20 is a vertical sectional view showing another embodiment of the water-saving device according to the present invention.

FIG. 21 is a vertical sectional view showing another embodiment of the water-saving device according to the present invention.

REFERENCE SIGNS LIST

-   A Water-saving device -   1 Tap -   11 Thread portion -   2 Attachment cover -   21 Thread groove -   22 Engagement stepped portion -   23 Helical groove -   25 Step portion -   3 Watertight gasket -   4 Pressure reducing piece (pressure control means) -   41 Base plate -   42 Flow path changing hole (water passage hole) -   42 a First water passage hole -   42 b Second water passage hole -   43 Protruding portion -   45 Water passage hole -   4A Porous body -   5 Spacer gasket -   6 Water-saving piece (discharge means) -   61 Collar -   62 Water discharge hole -   62 a Annular water passage hole portion -   62 b Circular arc water passage hole portion -   62 c Corrugated annular water passage hole portion -   62 d Corrugated circular arc water passage hole portion -   63 Buffering portion -   64 Outer end face -   65 Adjustment portion -   66 Thread portion -   67 Tool engagement recess -   68 Screw hole -   68 a Helical groove -   69 Connecting portion -   69 a Connecting portion -   7 Adjusting member -   71 Thread portion -   72 Adjustment portion -   73 Tool engagement recess -   74 Gasket -   8 Single-pore water passage hole portion -   80 Flange portion -   81 Water passage hole -   81 a Top end opening -   82 Water passage hole -   83 Upstream end face -   84 Circular recess -   8A Single-pore water passage hole portion -   9 Porous body (porous water passage hole portion) -   9A Porous water passage hole portion -   9B Water passage hole

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a water-saving device according to the present invention will be described in detail based on the accompanying drawings of embodiments; however, the present invention is not limited to this description.

FIG. 1 is an exploded perspective view showing an exemplary water-saving device A according to an embodiment of the present invention, and FIG. 2 is a vertical sectional view of the device in FIG. 1.

Here, in the drawings, like members will be denoted by like reference signs, and redundant descriptions will be omitted.

The water-saving device A includes a cylindrical tube-like attachment cover 2 that can be mounted to a water outlet at the tip of a tap 1 or the like for spouting water and is open at its top and bottom, a water-saving piece 6 serving as a discharge means that is internally fitted to the attachment cover 2 and has at least one water discharge hole 62, and a watertight gasket 3 for preventing a water leak that is provided between the tap 1 and the attachment cover 2.

Furthermore, a pressure reducing piece 4 serving as a pressure control means, in which a flow path changing hole 42 that changes the direction of water spouted from the tap 1 is formed, is provided in the attachment cover 2. This pressure reducing piece 4 is provided upstream of the water-saving piece 6 with a space kept between them by a spacer gasket 5.

Hereinafter, each member will be described in detail.

A thread portion 11 is formed at a tip portion of the tap 1, and a thread groove 21 is formed on an inner circumference of a tube-like portion, which serves as an attachment means that can be screwed onto the thread portion 11, of an inner wall of an upper end part of the attachment cover 2.

Otherwise, in the case where the thread portion 11 is not formed at the tip portion of the tap 1, if a threaded hole (omitted from the drawings) penetrating through a side wall of the upper end part of the attachment cover 2 is formed beforehand, and an attachment screw (omitted from the drawings) is screwed from the outer side into this threaded hole (omitted from the drawings) to press against an outer wall of the tip portion of the tap 1, the attachment cover 2 can be attached to the tip portion of the tap 1.

It should be noted that although the attachment cover 2 of this embodiment is formed into the shape of a cylindrical tube, the shape is not particularly limited and can be formed as appropriate in accordance with the design of the tap 1 or the like.

The watertight gasket 3 is configured of a rubber ring having the same diameter as the diameter of the tap 1. This watertight gasket 3 sits on the pressure reducing piece 4, and as a result of screwing the thread groove 21 of the attachment cover 2 onto the thread portion 11 of the tap 1, the rubber ring 3 is interposed between a base plate 41 and the tap 1 in pressure contact with them and thus prevents leaking of water from a gap therebetween.

It should be noted that since all that is required of the watertight gasket 3 is to prevent leaking of water from the gap between the tap 1 and the attachment cover 2, it is also effective to fill a sealing material or wind watertight tape instead of using this watertight gasket 3.

Furthermore, an engagement stepped portion 22 with which a collar 61 formed at an upper end of the water-saving piece 6 can engage is formed at an appropriate position of an inner side wall of the attachment cover 2, and the pressure reducing piece 4 and the water-saving piece 6 are arranged in this attachment cover 2 with a space K (see FIG. 3) kept between them by the spacer gasket 5.

The pressure reducing piece 4 comprises the disc-like base plate 41 and a protruding portion 43 having a smaller diameter than the base plate 41 and protruding upward from the center of the base plate 41. Then, the watertight gasket 3 is interposed between the base plate 41 protruding outward in the radial direction like a flange and the tip of the tap 1.

Moreover, the diameter of the base plate 41 is formed in accordance with various inner diameters of the attachment cover such that it is brought into internal contact with the attachment cover 2, and therefore is not particularly limited, and also the diameter and height of the cylindrical protruding portion 43 are formed in accordance with various inner diameters of the attachment cover 2 and therefore are not particularly limited.

The flow path changing hole 42 serving as a water passage hole is formed so as to penetrate from a side face of the protruding portion 43 to the center of the base plate 41. One end of this flow path changing hole 42 is formed as a single hole, and the other end branches into a plurality of holes in communication with each other. The flow path changing hole 42 of this embodiment is configured of first water passage holes 42 a in a horizontal direction that are formed to radially and equidistantly extend from the side face of the protruding portion 43 toward the inside thereof and a single second water passage hole 42 b into which these first water passage holes 42 a join at a central inner part. The second water passage hole 42 b is in communication with the center of the base plate 41.

The number of branches, that is, the number of first water passage holes 42 a can be selected as appropriate depending on the extent of pressure reduction; however, the number of branches can be at least two or more, and preferably, the branches are equidistantly arranged in an even number of different directions, for example, the branches preferably are equidistantly arranged in four different directions so that water streams flowing in opposite directions collide with each other, thus reducing the pressure.

Since the size of the flow path changing channel 42 influences the volume of water saved and the amount of the pressure reduction of the water spouted from the tap 1 or the like, a hole diameter suited for the intended purpose can be selected as appropriate; however, generally, a range of 1 to 5 mm and particularly a range of 1.5 to 3.2 mm is preferable.

Furthermore, there is no particular limitation to the material for the pressure reducing piece 4 as long as that piece is formed of a corrosion-resistant material. Specific examples of such material include simple substances or compounds of corrosion-resistant metal materials such as stainless steel, brass, copper, silver and gold, synthetic rubbers such as styrene-butadiene rubber and elastomer, synthetic resins such as polyvinyl chloride, polyester or polypropylene, ceramics and the like.

The spacer gasket 5 is formed into a ring shape having the same diameter as the base plate 41 of the pressure reducing piece 4, and the space K between the pressure reducing piece 4 and the water-saving piece 6 is maintained by interposing this spacer gasket 5 between them.

The water-saving piece 6 is formed into a solid cylindrical shape that is internally fitted to the attachment cover 2, and a buffering portion 63 directly hit by water drawn out of the flow path changing hole 42 is formed in its central part.

The buffering portion 63 of the embodiment shown in FIGS. 1 and 2 is illustrated by way of example as being a blocked region that is formed in the center of the water-saving piece 6 and has no through hole in a vertical direction and thereby preventing water from being discharged from this buffering portion 63.

Multiple vertically penetrating water discharge holes 62 are formed around this buffering portion 63, and therefore the water buffered by hitting the buffering portion 63 is discharged through the water discharge holes 62. Specifically, the water discharge holes 62 shown are arranged at a predetermined spacing in an outer peripheral part of the buffering portion 63, in two circles that are concentric with the water-saving piece 6 and have different diameters; however, the number and diameter of the water discharge holes 62 are increased or decreased as appropriate depending on the discharge rate of buffered water discharged.

As a result of arranging the water discharge holes 62 in such a concentric circle, a desired discharge rate of water can be obtained, and furthermore, buffered water discharged from the water discharge holes 62 can be discharged uniformly.

Although there is no particular limitation to the shape of the water-saving piece 6, it is generally desirable that the thickness in the vertical direction is within a range of 2 to 15 mm, particularly within a range of 3 to 10 mm, and most preferably within a range of 5 to 7 mm. Moreover, there is no particular limitation to the material for the water-saving piece 6 as long as that piece is formed of a corrosion-resistant material, which include simple substances or compounds of corrosion-resistant metal materials such as stainless steel, brass, copper, silver and gold, synthetic rubbers such as styrene-butadiene rubber and elastomer, synthetic resins such as polyvinyl chloride, polyester or polypropylene, ceramics and the like.

Moreover, preferably, the size of the water discharge holes 62 is generally within a range of 0.1 to 2 mm and particularly within a range of 0.6 to 1.2 mm. Also, the diameter and number of the water discharge holes 62 can be optimally formed by considering the diameter and thickness of the water-saving piece, the size of the tap and the like, and it is only necessary that at least one water discharge hole 62 is formed.

Specifically, since the buffering portion 63 directly hit by water supplied from a water pipe (omitted from the drawings) is formed at an appropriate position in the center of the water-saving piece 6, multiple water discharge holes 62 can be formed around the buffering portion 63, and, for example, in the case where the water-saving piece 6 is cylindrical, the buffering portion 63 can be provided in its central part, and one or more water discharge holes 62 can be arranged being spaced out in one to three concentric circles in the outer peripheral part of the buffering portion 63.

The thus-configured water-saving device A of the present invention works in the following manner.

Referring to FIG. 3, which is an enlarged sectional view of the water-saving device A of the present invention shown in FIGS. 1 and 2 is attached to the tap 1 or the like in use, water spouted from the tap 1 or the like first directly hits an upper face of the protruding portion 43 of the pressure reducing piece 4, and thus the direction of water is changed once and the water stream or water pressure is reduced. Water whose water pressure has been reduced passes through the plurality of flow path changing holes 42 formed in the side face of this protruding portion 43, which further changes the direction of water, and then, water whose pressure has been reduced is drawn out downward from the center of the base plate 41.

Next, the pressure-reduced water that has been drawn out of the flow path changing hole 43 directly hits the buffering portion 63 of the water-saving piece 6, so that the direction of water is changed and the water is buffered, and at the same time, the water stream or water pressure is reduced once again. Then, the water temporarily collects in the clearance K formed between the water-saving piece 6 and the pressure reducing piece 4 by the spacer gasket 5, and the water pressure of the pressure-reduced water is thus maintained at a constant level.

Then, this buffered water whose pressure has reliably been reduced is discharged to the outside through the water discharge holes 62 of the water-saving piece 6.

As described above, the water-saving device A of this embodiment can save water by suppressing the discharge rate without changing the usage feel of a faucet (omitted from the drawings), that is, without the need to adjust the faucet every single time, and discharge water after reducing the pressure of forceful water spouted from the tap 1 or the like with the pressure reducing piece.

Accordingly, buffered water discharged through such a water-saving piece apparatus is not only gentle to the skin even when it directly hits the skin but also has a beautiful appearance, and in particular, provides such an effect that irritation to the skin can be minimized for the users having tender skin, such as infants and women.

Moreover, since the pressure reducing piece 4 is provided on the upstream side of the water-saving piece 6 with a space kept between them by the gasket 3, pressure-reduced water whose pressure has been reduced by the pressure reducing piece 4 temporarily collects in the space K, and thus the water pressure of the pressure-reduced water is maintained at a constant level. Therefore, pressure-reduced water of a constant water pressure is supplied to the water-saving piece 6 on the downstream side independently of variations in the water pressure in the tap 1 or the like, so that buffered water discharged to the outside from the water-saving piece 6 can be discharged stably with a constant water pressure, and consequently, buffered water having a more gentle feel can be provided with irritation to the user being further suppressed.

Furthermore, since one end of the flow path changing hole 42 comprises a single hole and the other end comprises multiple holes branching in the middle, the pressure of water spouted from the tap 1 or the like can be controlled by automatically reducing the pressure without changing the usage feel of the faucet.

Moreover, since the blocked buffering portion 63 directly hit by low-pressure water drawn out of the flow path changing hole 42 is formed at an appropriate position in the center of the water-saving piece 6, the low-pressure water drawn out of the flow path changing hole 42 hits the buffering portion 63 and is then discharged to the outside through the water discharge holes 62. Thus, if the water-saving device A is mounted to the tap 1 of an automatic faucet, a manual, mixing faucet or the like of, for example, a toilet (omitted from the drawings), buffered water is discharged without splashing, and therefore the water can be smoothly supplied to a tank or the like (omitted from the drawings) without staining the vicinity of the tank.

According to the water-saving device A of this embodiment, since the multiple water discharge holes 62 are formed and arranged in the outer peripheral part of the buffering portion 63 in one or more concentric circles, a desired discharge rate can be obtained. Furthermore, the buffered water can be uniformly discharged from the water discharge holes 62.

It should be noted that although the water-saving device A of this embodiment is described using the case where the protruding portion 43 of the pressure reducing piece 4 protrudes upward as an example, the pressure reducing piece 4 can also be turned upside down and attached with the protruding portion 43 protruding downward.

The present invention is not limited to the above-described embodiment. Other embodiments will be described below. It should be noted that members corresponding to the same members as those of the above-described embodiment will be denoted by the same reference signs, and respective descriptions thereof will be omitted.

The water-saving device A of an embodiment shown in FIGS. 4 and 5 includes an attachment cover 2, a pressure reducing piece 4, a water-saving piece 6, a watertight gasket 3 and a spacer gasket 5.

The pressure reducing piece 4 has a water passage hole 45 into the center of which multiple first water passage holes 42 a join. This water passage hole 45 is formed into a substantially conical shape gradually decreasing in diameter from the downstream side toward the upstream side.

A substantially conical adjustment portion 65 protrudes from the center on the upstream side of the water-saving piece 6, and water discharge holes 62 are arranged in the circumferential direction of the water-saving piece 6 around this adjustment portion 65 serving as a center. Moreover, a thread portion 66 is formed in an outer circumferential face of the water-saving piece 6, and this thread portion 66 is detachably screwed to a helical groove 23 serving as an attachment means that is formed in a lower part of an inner circumferential face of the attachment cover 2.

Therefore, the adjustment portion 65 of the water-saving piece 6 faces the inside of the water passage hole 45 of the pressure reducing piece 4, and a conical and ring-shaped second water passage hole 42 b is formed by a clearance between the adjustment portion 65 and the water passage hole 45. It should be noted that the pressure reducing piece 4 and the water-saving piece 6 constitute the pressure control means, and pressure adjustment is made with the water passage hole 45 of the pressure reducing piece 4 and the adjustment portion 65 of the water-saving piece 6.

A tool engagement recess 67 in which a tool such as a Phillips screwdriver or a flat blade screwdriver, which are omitted from the drawings, engages is formed in the downstream end face (lower surface) of the water-saving piece 6. It should be noted that this tool engagement recess 67 may have an engagement structure corresponding to a special tool in order to prevent tampering.

As described above, the water-saving device A of this embodiment is configured so that the adjustment portion 65 can be moved toward or away from a circumferential surface of the water passage hole 45 by turning the water-saving piece 6 with a tool engaged in the tool engagement recess 67.

With such a water-saving device A, the pressure on the downstream side of the pressure reducing piece 4, that is, the secondary pressure can be adjusted by changing a opening area of the second water passage hole 42 b by turning the water-saving piece 6 by operating a tool. In other words, with such a water-saving device A, pressure adjustment of the pressure adjustment means can be made by an external operation.

The water-saving device A according to an embodiment of the present invention shown in FIGS. 6 and 7 includes an attachment cover 2, a pressure reducing piece 4, a water-saving piece 6, a watertight gasket 3, a spacer gasket 5 and an adjusting member 7.

A pressure reducing piece having the configuration shown in FIGS. 4 and 5 described above is adopted as the pressure reducing piece 4, in which a plurality of first water passage holes 42 a and a water passage hole 45 are provided.

A screw hole 68 serving as an adjusting member fitting hole that penetrates through the water-saving piece 6 is formed in the center of the water-saving piece 6. A helical groove 68 a is formed in an upper part of an inner circumferential face of this screw hole 68, and a thread portion 71 of the adjusting member 7 configured of a small screw-like body is screwed in this helical groove 68 a so as to be able to advance and retreat. A substantially conical adjustment portion 72 that faces the inside of the water passage hole 45 is formed at the tip of an upper part of the adjusting member 7.

Moreover, a tool engagement recess 73 is formed in a lower surface (an end face on the outside side) of the adjusting member 7 so that the adjustment portion 72 can be moved toward or away from a circumferential surface of the water passage hole 45 by turning the adjusting member 7.

It should be noted that in the water-saving device A of this embodiment, the pressure reducing piece 4 and the adjusting member 7 constitute the pressure control means, and pressure adjustment is made with the water passage hole 45 of the pressure reducing piece 4 and the adjustment portion 72 of the adjusting member 7.

Watertight processing for imparting watertightness is applied to, or a gasket 74 is disposed at non-thread portions on the inner circumferential face of the screw hole 68 and an outer circumferential face of the adjusting member 7.

With such a water-saving device A, the pressure on the downstream side of the pressure control means, that is, the secondary pressure of water flowing between the pressure reducing piece 4 and the water-saving piece 6 can be adjusted by advancing or retreating the adjusting member 7 by turning it by an external operation with a tool. With such a water-saving device A, pressure adjustment can be made by a smaller external operation than that of the above-described embodiment because the adjusting member 7 that is turned is constituted by a small screw-like body.

The water-saving device A shown in FIGS. 8 and 9 includes an attachment cover 2, a porous body 4A serving as the pressure control means, a water-saving piece 6 and a gasket 3.

The porous body 4A is configured of a substantially disc-like porous body made of an open-cell porous ceramic. Numerous minute pores of the porous body 4A perform the function of the water passage hole 42 of the water-saving device A according to the above-described embodiment. It should be noted that no pressure adjustment means is provided in the water-saving device A of this embodiment.

In this manner, water pressure can be effectively reduced by adopting the porous body 4A as the pressure control means. Moreover, the porous body 4A can provide a filtering effect of removing foreign matter and impurities in water.

The water-saving device A shown in FIGS. 10 and 11 includes an attachment cover 2, a porous water passage hole portion 9, a single-pore water passage hole portion 8, a water-saving piece 6 and an adjusting member 7.

The porous water passage hole portion 9 is configured of a substantially disc-like porous body made of an open-cell porous ceramic.

The single-pore water passage hole portion 8 is integrally disposed at a lower part of the porous water passage hole portion 9 and holds the porous water passage hole portion 9. A flange portion 80 having a large diameter is provided in an outer circumferential part of the single-pore water passage hole portion 8, and this flange portion 80 engages a step portion 25 provided in an inner circumferential face of the attachment cover 2 from above.

Moreover, a substantially conical water passage hole 81 is formed in the center of a downstream end face of the single-pore water passage hole portion 8. A top end opening 81 a of this water passage hole 81 is connected with the numerous pores of the porous water passage hole portion 9. An outer circumferential face of the single-pore water passage hole portion 8 provides watertightness between itself and the inner circumferential face of the attachment cover 2.

A vertical screw hole 68 penetrating through the water-saving piece 6 is formed in the center of the water-saving piece 6. A thread portion 71 of the adjusting member 7 is screwed to a helical groove 68 a formed in an upper part of an inner circumferential face of this screw hole 68. Then, an adjustment portion 72 faces the inside of the water passage hole 81, and a conical and ring-shaped second water passage hole 42 b is formed between the adjustment portion 72 and the water passage hole 81.

It should be noted that in the water-saving device A of this embodiment, the porous water passage hole portion 9, the single-pore water passage hole portion 8, and the adjusting member 7 constitute the pressure adjustment means, and pressure adjustment is made with the water passage hole 81 of the single-pore water passage hole portion 8 and the adjustment portion 72 of the adjusting member 7.

The use of the porous water passage hole portion 9 as part of the pressure control means makes it possible to effectively reduce water pressure and to obtain the filtering effect of removing foreign matter and impurities in water.

Moreover, by an external operation with a tool, the adjusting member 7 can be turned with a smaller force to adjust the secondary pressure.

The water-saving device A shown in FIGS. 12 and 13 includes an attachment cover 2, a porous water passage hole portion 9A, a single-pore water passage hole portion 8A, a water-saving piece 6 and an adjusting member 7.

The porous water passage hole portion 9A is a filter-like sheet that has a large number of water passage holes 9B extending therethrough and is made of, for example, a silicon resin, an elastomer resin or a rubber resin. The porous water passage hole portion 9A is formed to have a corrugated sectional shape so that it has elasticity and deforms under stress (expands and contracts flexibly). Moreover, an edge of the porous water passage hole portion 9A is fixed to an upper part of the single-pore water passage hole portion 8A that is formed to have a small diameter.

The single-pore water passage hole portion 8A is integrally disposed at a lower part of the porous water passage hole portion 8A. The upstream side of the single-pore water passage hole portion 8A is formed into a substantially bay-like shape, and a substantially conical water passage hole 82 is formed in the center of a downstream end face thereof. This water passage hole 82 is in communication with an upstream end face 83 formed into the substantially bay-like shape and a circular recess 84 formed in the downstream end face.

Once a water pressure at or above a certain level acts on the porous water passage hole portion 9A, this portion expands so as to bulge toward the downstream side and reduce the water pressure (see FIG. 13( b)).

A screw hole 68 having the above-described helical groove 68 a is provided in the water-saving piece 6. Then, the above-described adjusting member 7 is screwed in this screw hole 68 so as to be able to advance and retreat.

It should be noted that the porous water passage hole portion 9A, the single-pore water passage hole portion 8A and the adjusting member 7 constitute the pressure control means, and pressure adjustment is made with the water passage hole 82 of the single-pore water passage hole portion 8A and the adjusting member 7.

With such a water-saving device A, the water pressure can be automatically controlled so as to be approximately constant by the porous water passage hole portion 8A that flexibly expands or contracts depending on the water pressure.

The water-saving devices A shown in FIGS. 14 to 20 are characterized by water discharge holes 62 of a water-saving piece 6. It should be noted that the exemplary water-saving devices A described below include an attachment cover 2, a watertight gasket 3, a pressure reducing piece 4, a spacer gasket 5 and a water-saving piece 6.

Individual water discharge holes 62 extending through the water-saving piece 6 of the water-saving device A shown in FIGS. 14( a) and 14(b) are formed so that their shapes in a downstream end face of the water-saving piece 6 and their transverse sectional shapes are substantially star-shaped.

As a result of forming the water discharge holes 62 to have a substantially star shape as described above, water discharged from each of the water discharge- holes 62 is subjected to a flow-straightening action and therefore released straight without splashing around or flying in curves.

In the water-saving device A shown in FIGS. 15( a) to 15(c), a water discharge hole 62 has connecting portions 69 in an inner end face (an upstream end face) of the water-saving piece 6. In other words, the water discharge hole 62 is configured of an annular water passage hole portion 62 a that is circumferentially formed to extend from a downstream end face of the water-saving piece 6 to an appropriate intermediate position in an axial direction, and circular arc water passage hole portions 62 b that are provided in the upstream end face while leaving the connecting portions 69 and are formed in communication with the annular water passage hole portion 62 a.

Thus, water discharged from the water discharge hole 62 provided in the water-saving piece 6 defines an approximately cylindrical tube-like shape or an approximately conical tube-like shape instead of a shower-like shape, and the discharged water looks as if it were a cylindrical or conical column of water, appears larger in volume than it really is, and furthermore, does not become clouded and therefore has transparency and looks beautiful.

In the water-saving device A shown in FIGS. 16( a) to 16(c), the outer end face of a water discharge hole 62 extending through the water-saving piece 6 has a substantially corrugated circumferential shape. In other words, the water discharge hole 62 is configured of a corrugated annular water passage hole portion 62 c that is circumferentially formed to extend from a downstream end face of the water-saving piece 6 to an appropriate intermediate position in the axial direction, and corrugated circular arc water passage hole portions 62 d that are provided in an upstream end face while leaving connecting portions 69 a and are formed to connect with the corrugated annular water passage hole portion 62 c.

Thus, water spouting from the corrugated annular water discharge hole 62 provided in the water-saving piece 6 defines an approximately cylindrical tube-like shape or a corrugated cylindrical tube-like shape instead of a shower-like shape, looks as if it were a cylindrical or corrugated cylindrical column of water, appears larger in volume than it really is, and furthermore, does not become clouded and therefore has transparency and looks beautiful.

The water-saving devices A shown in FIGS. 17 to 20 are characterized by an outer end face of a water discharge means. It should be noted that the exemplary water-saving devices A described below include an attachment cover 2, a watertight gasket 3, a pressure reducing piece 4, a spacer gasket 5 and a water-saving piece 6.

The water-saving piece (water discharge means) 6 of the water-saving device A shown in FIGS. 17( a) and 17(b) has a water discharge hole 62 extending therethrough from an upstream end face to a downstream end face, and moreover, the downstream end face, that is, an outer end face 64 thereof is formed concavely toward the upstream side. Preferably, a vertical sectional shape that is defined by the concavely curved outer end face 64 of this water discharge means 6 is cycloidal.

After a faucet having such a water-saving device A attached to its water outlet is closed to stop releasing water, remaining water droplets adhering to the outer end face of the water discharge means 6 quickly flow along the curved outer end face 64 of the water discharge means 6 toward an outer end peripheral edge before evaporating, and then drip from this outer end peripheral edge. Thus, due to dripping of water from the outer end peripheral edge, deposition of components, such as foreign matter and impurities, contained in the supplied water on the outer end face and the like of the water discharge means can be suppressed.

Moreover, since water is spouted from the water discharge hole 62 in such a manner that water on the inner side of the water discharge hole 62 is freed from the outer end face 64 first, the released water can be prevented from diverging.

The water discharge means 6 of the water-saving device A shown in FIGS. 18( a) and 18(b) has a water discharge hole 62 extending therethrough from an upstream end face to a downstream end face, and an outer end face 64 thereof is formed concavely. A concave surface of this outer end face 64 is formed eccentrically or asymmetrically with respect to the center of the outer end face 64 of the water discharge means 6.

Thus, since the outer end face 64 of the water discharge means 6 is formed as an eccentric concave surface, after a faucet having such a water-saving device A attached to its water outlet is closed to stop releasing water, remaining water droplets adhering to the outer end face of the water discharge means 6 quickly flow toward an outer end peripheral edge on one side of the water discharge means 6 before evaporating, due to the eccentrically concave outer end face 64 of the water discharge means 6, and then drip from the outer end peripheral edge on this side. As a result of employing a configuration in which the water droplets drip from the outer end peripheral edge on one side as described above, deposition of components, such as foreign matter and impurities, contained in the supplied water on the outer end face and the like of the water discharge means can be suppressed.

Moreover, since water is spouted from the water discharge hole 62 in such a manner that water on the inner side thereof is freed from the outer end face 64 first, the released water can be prevented from diverging.

The outer end face 64 of the water discharge means 6 of the water-saving device A shown in FIGS. 19( a) and 19(b) is formed convexly. The water discharge means 6 has a water discharge hole 62 extending therethrough from an upstream end face to a downstream end face (an outer end face) 64, and the outer end face 64 is formed convexly toward the downstream side.

Therefore, after a faucet having such a water-saving device A attached to its water outlet is closed to stop releasing water, remaining water droplets adhering to the outer end face of the water discharge means 6 quickly flow toward the outer end center of the water discharge means 6 before evaporating, and then drip from this outer end center. Accordingly, deposition of components, such as foreign matter and impurities, contained in the supplied water on the outer end face and the like of the water discharge means can be suppressed.

Moreover, since water is discharged from the water discharge hole 62 in such a manner that the discharged water on the outer side is freed from the outer end face first, the released water can be diverged.

In the water-saving device A shown in FIGS. 20( a) and 20(b), a downstream end face (an outer end face) 64 of a water-saving piece 6 serving as the water discharge means has protruding portions 64a provided only in respective water discharge hole 62 portions. In other words, the water-saving piece 6 has the water discharge holes 62 extending therethrough from an upstream end face to the outer end face 64, and the protruding portions 64a are formed only in regions around the above-described water discharge holes 62 on the outer end face so as to protrude toward the downstream side.

Preferably, vertical sections defined by the regions around the water discharge holes 62 on the convexly curved outer end face of the water-saving piece 6 have cycloidal shapes.

Therefore, after a faucet having such a water-saving device A attached to its water outlet is closed to stop releasing water, remaining water droplets adhering to the outer end face 64a of the water discharge means, that is, the water-saving piece 6 quickly drip from the regions around the water discharge holes 62 on the outer end face of the water-saving piece 6 before evaporating, and thus, water does not spread into portions other than the convex portions 64a on the outer end face of the water-saving piece 6, and deposition of components, such as foreign matter and impurities, contained in the supplied water on the outer end face 64 and the like of the water-saving piece 6 is suppressed.

The present invention is not limited to the above-described embodiments. For example, although the case where the constituent members are configured of separate members is described in each of the above-described embodiments, the constituent members may be integrally formed of a single member as shown in FIG. 21, by a shaping process that employs, for example, laser beam machining. It should be noted that in FIG. 21, portions having the same functions as the members shown in FIG. 3 are denoted by the same reference signs, and descriptions thereof are omitted. 

1. A water-saving device that can be mounted to a water outlet of a tap or the like, comprising a pressure control means that has a water passage hole and a water discharge means that is provided downstream of the pressure control means and has a water discharge hole, wherein water supplied from the water outlet passes through the water passage hole of the pressure control means, thereby effecting a pressure reduction, so that a water pressure on a downstream side of the pressure control means is lower than that on an upstream side, and the water whose pressure has been reduced is discharged from the water discharge hole.
 2. The water-saving device according to claim 1, wherein the pressure control means comprises a pressure adjustment means that adjusts a pressure of water supplied from the water outlet within the water-saving device.
 3. The water-saving device according to claim 2, wherein the pressure adjustment means comprises the water passage hole that is formed into an substantially conical shape in a center on the downstream side of the pressure control means and an adjustment portion that protrudes from the upstream side of the water discharge means and faces an inside of the water passage hole, and an opening area of a clearance in the water passage hole through which water can pass can be changed to adjust a water pressure in the water passage hole by moving the adjustment portion toward or away from the water passage hole by an external operation.
 4. The water-saving device according to claim 2, wherein the pressure adjustment means comprises the water passage hole that is formed into an substantially conical shape in a center on the downstream side of the pressure control means and an adjusting member that is fitted in an adjusting member fitting hole formed in a center of the water discharge means, penetrating therethrough from an upstream end face to a downstream end face, the adjusting member has an adjustment portion that faces an inside of the water passage hole, and an opening area of a clearance in the water passage hole through which water can pass can be changed to adjust a water pressure in the water passage hole by advancing or retreating the adjustment portion with respect to the water passage hole by an external operation.
 5. The water-saving device according to claim 1, wherein the pressure control means comprises a pressure reducing piece that is provided in an attachment cover that can be mounted to the water outlet, and the water passage hole is configured of a flow path changing hole that is formed in the pressure reducing piece so as to change a direction of water spouted from the water outlet.
 6. The water-saving device according to claim 1, wherein the pressure control means comprises a porous body that water can permeate, and pores of the porous body constitute the water passage hole.
 7. The water-saving device according to claim 1, wherein the pressure control means comprises a filter-like member that has a large number of water passage holes extending therethrough from a front side to a back side and that flexibly expands and contracts.
 8. The water-saving device according to claim 1, wherein a downstream end face of the water discharge means is formed concavely or convexly.
 9. The water-saving device according to claim 1, wherein the water discharge means has water discharge holes that are arranged in an annular or corrugated annular shape in the downstream end face.
 10. A water-saving device comprising an attachment cover that can be mounted to a water outlet of a tap or the like, a watertight gasket for preventing a water leak between the water outlet and the attachment cover, a pressure reducing piece that is internally fitted to the attachment cover and has at least one water passage hole, and a water-saving piece that is internally fitted to the attachment cover and has at least one water discharge hole, wherein the water passage hole forcibly changes a flow direction of water that has been supplied from the water outlet and has flown into the attachment cover, and a water pressure is reduced by the forcible flow path change.
 11. The water-saving device according to claim 10, wherein the pressure reducing piece is disposed upstream of the water-saving piece with a space kept between them by a gasket.
 12. The water-saving device according to claim 10, wherein a buffering portion that pressure-reduced water drawn out of the water passage hole that performs a forcible flow path change directly hits and is therefore buffered is formed at an appropriate position in a center of the water-saving piece, and water discharge holes are formed around the buffering portion so that buffered water that has hit the buffering portion is discharged through the water discharge holes.
 13. The water-saving device according to claim 12, wherein the water discharge holes are arranged in one or more concentric circles in an outer peripheral part of the buffering portion. 